How to generate Archive library of libclang_rt.dfsan-x86_64.a in bit-code format.

Dear Developers,

I would like to beg suggestions/guidance about how I can generate the archive library of libclang_rt.dfsan-x86_64.a (LLVM Dataflow Sanitizer Library) in LLVM IR bit-code format by myself, which actually also means that how I can get LLVM IR Bit-code of each source files of this Dataflow Sanitizer Library.

I am eagerly waiting for your kind response. Thank you.